US3694020A

US3694020A - Syphon or solids having a piston which is connected with a suspension arrangement

Info

Publication number: US3694020A
Application number: US36320A
Authority: US
Inventors: Klaus Becker; Karlheinz Wolski
Original assignee: Demag AG
Current assignee: Mannesmann Demag AG
Priority date: 1969-05-13
Filing date: 1970-05-11
Publication date: 1972-09-26
Anticipated expiration: 1989-09-26

Abstract

A syphon for solids includes a piston movable in a cylinder to produce an underpressure which is communicated to an attachment for the cylinder in order to permit the attachment to engage the solid material to be lifted. The syphon includes a locking mechanism which connects the cylinder space with the piston during every second stroke of the piston to prevent the formation of a vacuum. The arrangement includes an auxiliary vacuum pump which is connected with the suction space of the cylinder and which is driven by a motor both of which are advantageously carried within the piston.

Description

United States Patent Becker et al.

[451 Sept. 26, 1972 [72] Inventors: Klaus Becker, Volmarstein; Karlheinz Wolski, Bochum-Langendreer, both of Germany [73] Assignee: DEMAG Aktiengesellschaft,

Duisburg, Germany [22] Filed: May 11, 1970 [21] Appl. No.: 36,320

[30] Foreign Application Priority Data May 13, 1969 Germany ..P 19 24 293.4

July 4, 1969 Germany ..P 19 34 033.1

Sept. 29, 1969 Germany ..P 19 49 065.4

Sept. 29, 1969 Germany ..P 19 49 064.3

Dec. 12, 1969 Germany ..P 19 62 273.2

[52] US. Cl....: ..294/64 R, 294/65 [51] Int. Cl. ..B66c l/02 [58] Field of Search ..294/64, 65; 417/321, 372;

214/1 BS, 1 BT, 6 P8, 8.5 D, 650 SG [56] References Cited UNITED STATES PATENTS 3,497,254 2/1970 Lutolf et a1 ..294/64 2,917,226 12/1959 Scheiterlein ..417/372 3,431,010 3/1969 Glanemann ..294/64 Primary ExaminerEvon C. Blunk Assistant Examiner-Johnny D. Cherry AttorneyMcGlew and Toren 57 ABSTRACT A syphon for solids includes a piston movable in a cylinder to produce an underpressure which is communicated to an attachment for the cylinder in order to permit the attachment to engage the solid material to be lifted. The syphon includes a locking mechanism which connects the cylinder space with the piston during every second stroke of the piston to prevent the formation of a vacuum. The arrangement includes an auxiliary vacuum pump which is connected with the suction space of the cylinder and which is driven by a motor both of which are advantageously carried within the piston.

13 Claims, 6 Drawing Figures 3,322,22 5/l 96 7 l'ngelen m1 ....177/20s PATENTEU SEPZB 3. 694,020

SHEET 3 [IF 4 Fig. 5

Inventors K1405 BECKER A4424 x/swz W04 510 PATENTEDSEPZB m2 3.694.020

SHEET U [1F 4 Inventors [441/5 5504 52 K421 HEM/Z W015i ArrOPAlE/s SYPHON R SOLIDS HAVING A PISTON WHICH IS CONNECTED WITH A SUSPENSION ARRANGEMENT SUMMARY OF THE INVENTION This invention relates in general to the construction of syphons and in particular to a new and useful syphon for solids having a suspension arrangement which is connected to a piston which is movable in a cylinder to create an underpressure and wherein the cylinder carries a sealing attachment which is adapted to lie against the material to be lifted, and wherein the cylinder is provided with a locking attachment which connects the underpressure space with the opposite side of the piston to prevent the piston from rising within the cylinder to form a vacuum.

Syphons of the type mentioned above have the advantage that they can be attached to any lifting device and the vacuum can be immediately formed for lifting without any loss of time. Connecting lines to a vacuum system or an electrical cable for driving a vacuum pump are not required in such a construction. However, it is a disadvantage of these syphons that the lifting times are limited particularly with porous materials, or in the case of a leaky sealing attachment.

In accordance with the present invention, a rapidly deployable syphon is equipped with a cylinder and piston which may be reciprocated within the cylinder for a practically unlimited amount of lifting times. This is accomplished by providing an auxiliary vacuum pump which is connected to the space which undergoes an underpressure during the movement of the piston and which is driven by a motor. The motor of the vacuum pump can be connected to a battery or to a power line and can be switched on by hand as soon as the piston has reached the given height within the cylinder. It can, however, also be switched on by an end switch which is actuated by the piston and upon reaching a predetermined height position. In the preferred form the motor and the vacuum pump are preferably attached within the syphon at the bottom of the piston. In most cases the piston is guided within the cylinder by a piston rod and the vacuum pump is arranged on one side of a centrally positioned piston rod and the motor on the other side is connected with the vacuum pump through a driving member such as a belt. Thus, two relatively large parts for the maintenance of the vacuum can be arranged in a protected area within the syphon, for example, within the piston head. The construction may also include one in which two piston rods are employed for guiding the movement of the piston within the cylinder, and in such arrangement the motor and the vacuum pump are located between the piston rods. This latter arrangement is recommended for relatively large syphons and the motor and the vacuum pump are of compact design and are coaxially connected with each other. The pump and the driving motor are advantageously equipped with cooling fins, and in order to enhance the cooling effect still more, it is appropriate that the pump include motor fan blades which are arranged to draw cooling air through the ventilating openings of the housing and to direct it along the motor and the vacuum pump.

Up to the time of the present invention syphons have been made of very heavy material because it was believed that a minimum weight is necessary in order to provide an adequate tight contact of the sealing means of the syphon with the material to be lifted. The syphon became so heavy that hoisting equipment or several persons were necessary to move the larger models from one place of storage to a place of use. The large weight of the syphon is a drawback particularly if the syphon is frequently exchanged for other load lifting devices.

It has been found that the use of a soft sealing attachment for the syphon permits it to be manufactured of relatively light-weight material, for instance, light metal or plastic. The cylinder is preferably divided into an upper and lower ring, and the upper ring which is provided with an extension which leads downwardly forms a housing for the lower ring and the piston. The use of a separable housing is is appropriate particularly for the manufacture of a syphon from a plastic material as the housing protects the sensitive parts, namely, the lower ring and the piston against mechanical damage. These parts arranged in a protective manner define the suction space of the syphon and such an arrangement provides a moisture resistant construction. By making the syphon a light metal or plastic, it is not necessary to paint these parts as was previously required when steel was used, for example. Polyamide is suitable as a plastic material which can be reinforced by the addition of glass fibers.

According to another feature of the invention, the lower ring of the cylinder is clamped between an extension of the housing part of the cylinder and a bottom which is fastened to the housing, preferably by screws. The bottom is advantageously made of a steel material and it is provided with a sealing attaching which, for example, may be engaged with it around the periphery thereof. The use of the heavy steel results in a low position of the center of gravity of the syphon. The bottom can easily be detached from the housing and therefore makes the replacement thereof very quick. The attachment which is used is preferably adapted to the material to be lifted. The bottom can be a ring or a plate which is provided with a connecting opening between the suction space and the space underneath the bottom. Underneath the bottom can also be arranged a swing plate having a suction space, defined in the radial direction by the sealing attachment and which is connected through a line with the suction space of the cylinder beneath the piston.

In order to obtain a proper seal, sealing devices are clamped between the cylinder-lower ring and the extension of the housing and also between the cylinderlower ring and the bottom. The seal clamped between the cylinder and the extension of the housing is the rim of a rolling diaphragm connected with the piston. This assures trouble-free sealing between the cylinder and the piston and no large friction resistance will occur if the piston is lifted in the cylinder.

Accordingly, it is an object of the invention to provide a syphon or lifting device particularly for solids which includes a piston which is movable within a cylinder to create an underpressure on one side thereof and which includes a sealing attachment connected to the cylinder adjacent the area of underpressure and having a connection between the underpressure area and the sealing means for engaging a solid object.

A further object of the invention is to provide a syphon which includes a piston movable within a cylinder to create an underpressure and a sealing at? tachment which is carried by the cylinder and adapted to engage the article through the use of a sealing effect produced by the underpressure and wherein the piston is guided by one or two piston rods within the cylinder and advantageously includes an auxiliary vacuum pump which is connected to the suction space and which is driven by a motor which is arranged within the cylinder.

A further object of the invention is to provide a syphon which is simple in design, rugged in construction, and economical to manufacture. The various features of novelty which characterize the invention are pointed out with particularlity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there are illustrated preferred embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a partial elevational and partial transverse sectional view showing the location of the piston in a downward position on the left-hand portion and in the upward position on the right-hand portion of a syphon constructed inaccordance with the invention;

FIG. 2 is a partial sectional view of a sealing attachment of another embodiment of the invention;

FIG. 3 is a sectional view of another embodiment of the invention;

FIG. 4 is a partial sectional view of anothe'r embodiment of sealing attachment;

FIG. 5 is a section taken on the line V--V of !FIG. 3; and

FIG. 6 is a view similar to FIG. 1 of another embodiment of the invention.

GENERAL DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings in particular the invention embodied therein in FIG. 1 comprises a syphon or lifting device generally designated 50 which includes a cylinder 1 having an outer or upper ring portion 1a and a lower or inner ring portion 1b. The upper portion includes a downwardly and inwardly extending extension 1c and between the extension 10 and the lower ring portion lb there is clamped a sealing or rolling diaphragm 15. The other end of the diaphragm is secured to a side of a piston 5 which is movable within this cylinder. In the embodiment of FIG. 1 two piston rods 7 and 7' provide guides at respective opposite sides of the cylinder for the piston 5. The

piston rods

7 and 7 are guided in sleeves 2a of a head portion for axial movement and each includes a sealing ring 9 formed as part of a venting valve 8. The rings 9 rest against the recesses 6 defined at the bottom of piston 5 when the piston is being pulled up by the piston rod 7 and 7' and therefore they seal off the suction space 14. The piston 5 is advantageously manufactured of a material such as glass fiber reinforced plastic preferably a polyamide.

In accordance with a feature of the invention, a vacuum pump 12 is provided with a flange connected motor- (not shown) and it is connected through a vacuum line to the space 14. The pump 12 is driven, for

example, through an electric motor control 54 which is connected through a cable 18 to a source of power. A manometer 13 is secured into a wall at the lower ring lb in an upward portion 1d of the ring in a vacuum sealed manner.

I The piston rods 7 and'7' are advantageously made of an aluminum alloy and extend through guides 2a of a plastic head portion 2 into a cover or cap 17 which is made of a plastic material in which they are secured in position such as by bolts. The top of the cap 17 is provided with a recess which accomodates a reinforcement ring or steel bolt 17a which is provided for engagement with a suspension device to support the whole mechanism. In the embodiment shown in FIG. 1, engageable means for lifting the device comprises the cap 17 with the ring 17a which is connected with the piston 5 through engagement of the widened top 7T of the piston rod 7' when the cap is lifted upwardly, to thus cause relative upward movement of the piston 5 relative to the cylinder 1 and to cause an underpressure below the piston 5 which is communicated to a sealing attachment 10 to permit it to engage and lift an object. It would, of course, also be possible to attach the sealing attachment 10 to the piston 5 rather than the cylinder 1 and connect the engageable means to lift the cylinder to effect the relative movement.

In accordance with a further feature of the invention the cap 17 carries a locking device generally designated 11 made of a rigid material such as steel which locks the piston 5 and thereby the

piston rods

7 and 7 and the piston 5 with the cylinder for every second stroke.

The piston rod 7 has at its upper end an eye similar to eye 16 in the FIG. 6 embodiment. The rod 7 leads through the cover 2 which is provided at the upper portion of the cylinder 1. The cover 2 is provided with a holding ring 28 in which are secured three control cams 24 in the form of bolts, the bolts being distributed over the periphery. The bolts project into control paths 21 of a rotatable ring 20. The rotatable ring 20 has on its upper portion a ring abatement 22 which is directed inwardly. The ring 22 is provided with openings 22A for projections 23 which are provided on cap 17. A helical spring 25 engages a bearing 29 which is secured on the cover 2 and presses a disc 26 always in an upward direction, and through a roller bearing 27. It also presses the rotatable ring 20 with its lower control part against the control cam 24.

The rotatable ring 20 is always charged by a spring force in a position which renders possible a turning of the ring ,20 upon lowering of the piston 5 and is provided with one or several axial openings for one or several projections 23 which are arranged at the cap 17.

The cylinder includes an extension 1d to which is secured a cylinder bottom such as by bolts. The cylinder bottom 3 carries a sealing attachment 10, which, for example, is vulcanized to the cylinder bottom or which can be cemented on or attached in a different manner. At least one opening (not shown) is directed through the cylinder bottom 3 and it leads into the suction space 14 and connects the interior space of the sealing attachment l0 therewith. This interior space is closed off downwardly by the plate 121 which is to be lifted.

In the embodiment indicated in FIG. 2, a swing plate 4 which is made of steel is suspended at the cylinder bottom 3 by a central pivotal bracket member. 56 which permits the sealing attachment to be pivoted. In this arrangement a vacuum line 19' connects to the vacuum space 14' at one end and connects through the bracket 56 into the swing plate 4 to the suction space 120.

In the embodiment of the device indicated at FIG. 3, there is provided a syphon generally designated 50 which includes a central single column or piston rod construction employing a piston 7 for guiding a piston 5' in a cylinder having an upper cylinder part la and a lower cylinder part 1b of a construction similar to that indicated in FIG. 1. In this construction a vacuum pump 12 is mounted on one side of the piston rod 7" in the piston 5 and a motor 24 is mounted on the other side. The motor 24 drives the pump through a driving member such as a sprocket chain or belt 25. The motor 24 and the vacuum pump 12 are provided with

cooling fins

12a and 24a respectively. As the vacuum pump operates only in the working position in which the piston 5' is uppermost, the vent openings 1e are provided in the upper part of the cylinder la. When the vacuum pump operates, the fan blades 26, as seen in FIG. 5, drive outside air through the vent openings 1e which are provided in the upper part la of the cylinder and move the air past the cooling fins of the vacuum pump and the motor. In this arrangement a sealing sleeve 27 is arranged above the top of the cylinder and protects the parts of the locking mechanism 11' which is similar to that of the embodiment of FIG. 1. A vacuum line 129 for the pump 12' extends through the piston for communicating with the vacuum space which will be left by the upward movement of the piston 5.

In FIG. 4, a further embodiment of pivotal sealing device is indicated with the parts being similar to that shown in FIG. 2 but being designated with a double prime. In this arrangement the sealing device 10 is pivotally suspended and interconnected through a flexible line 9 to the cylinder bottom 3" which provides a communication between the vacuum space 14" and the sealing space 120". i

In the embodiment illustrated in FIG. 6, there is provided a syphon generally designated 50" which includes a resistant sealing attachment 19" which is connected through a line 19" to communicate the vacuum 14" with the sealing space 20". In this arrangement the vacuum pump 12 and the flange connected motor 24 are mounted on the exterior of the cylinder and connected with the suction space 14" through a vacuum line 29". A check valve 28 is provided in the vacuum line 29". A ventilating Hood 30 is attached to the upper end of the cylinder at a cover 2. The syphon shown in FIG. 6, is essentially made of steel and due to its greater weight makes possible the use of a resistant sealing attachment 10". The suspension device 16 is rotatably attached to a centrally arranged piston rod 7". An actuating device 60 for venting valve 62 is located in the cylinder bottom 3" at which the swing plate 4" is suspended so that it can pivot. One or more handles 27 which are shown in a four shortened condition are employed to provide means for positioning the syphon precisely on the material to be lifted.

What is claimed is:

1. A vacuum lifter for lifting articles, comprising a cylinder, a piston movable in said cylinder in order to produce an underpressure in said cylinder on one side of said piston, a sealing attachment carried by one of said piston and cylinder and adapted to engage the article to be lifted with suction engagement therebetween produced by relative movement of said piston and said cylinder, conduit means connecting said cylinder at the underpressure side of said piston with said sealing attachment for providing an underpressure suction for engagement of the article, engageable means associated with said piston and cylinder for lifting them when said sealing attachment is engaged with an article and for causing relative movement of said piston and cylinder as the article is lifted, and an auxiliary vacuum pump mounted on said piston having a suction connected to said cylinder at the underpressure side of said piston for providing an additional underpressure to said sealing attachment for engagement of the article.

2. A vacuum lifter, according to claim 18, including a rolling diaphragm connected between the top of said piston and said cylinder on the interior of said cylinder, said engageable means including a cap positioned on the top of said cylinder, at least one connecting rod connected between said piston and said cap and guided in sealing engagement through the top of said cylinder, said sealing attachment being carried on said cylinder, said piston being hollow, said auxiliary vacuum pump being mounted within said hollow piston.

3. A vacuum lifter, according to claim 1, including a motor for driving said pump, said pump and said motor being attached to said piston.

4. A vacuum lifter, according to claim 1, including a piston rod for guiding the movement of said piston in said cylinder, a driving motor for driving said pump, said pump being located on one side of said piston rod, said motor being located on the other side of said piston rod, and a driving member connected between said motor and said pump.

5. A vacuum lifter, according to claim 1, including at least two piston rods in said cylinder for guiding said piston, a driving motor for driving said pump connected to said pump, said pump and said motor being located within said piston between said piston rods.

6. A vacuum lifter, according to claim 1, including a motor connected to said pump for driving said pump, said pump and said motor having cooling fins for increasing the heat transfer therefrom.

7. A vacuum lifter, according to claim 1, wherein said cylinder is divided into an upper ring portion and a lower ring portion, said lower ring portion having an exterior of said lower ring portion forming a housing for said piston.

8. A vacuum lifter, according to claim 1, wherein said piston and said cylinder are made of a plastic material.

9. A vacuum lifter, according to claim 1, wherein said cylinder comprises an upper cylinder portion and a lower cylinder portion, said upper cylinder portion including an inward extension, said lower cylinder portion being clamped between said extension and the lower portion of said upper cylinder portion.

10. A vacuum lifter, according to claim 1, including a bottom connected to said cylinder, said cylinder having an upper cylinder portion and a lower portion which is connected to said bottom by screws.

said cylinder is made of an upper portion and a lower portion, said upper portion having an intermediate extension extending downwardly around the upper portion of said lower portion, and a rolling diaphragm connected between the extension and said lower portion and said piston.

Claims

11. A vacuum lifter, according to claim 1, including a bottom closing said cylinder made of a steel material.

12. A vacuum lifter, according to claim 1, wherein said cylinder is made of an upper portion and a lower portion, said upper portion including a downward extension extending exteriorly of said lower portion, and a bottom connected to said lower portion.

13. A vacuum lifter, according to claim 1, wherein said cylinder is made of an upper portion and a lower portion, said upper portion having an intermediate extension extending downwardly around the upper portion of said lower portion, and a rolling diaphragm connected between the extension and said lower portion and said piston.